Log Message:-----------doc/usage.txt improvements
Patch by Greg Sabino Mullane, applied with minor modifications.
Modified Files:-------------- pgbouncer/doc: usage.txt (r1.9 -> r1.10) (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgbouncer/pgbouncer/doc/usage.txt?r1=1.9&r2=1.10)
